Problem With Force FX Kylo Ren Lightsaber...?

Has anyone else had a problem with one of these? I have gone through TWO of them and they both have the same problem. After a few minutes of use (straight out of the box, I might add), they take to switching off on their own. I don't mean the powering down feature. I mean they switch off sometimes just seconds after being activated. I was given one for Christmas that had this problem. I exchanged it for a replacement at Toys R Us and now the replacement is doing the same thing. Starting to smell like a design flaw. Any thoughts from anyone...?

Well...please forgive the obviousness here, but on my other force fx this is generally a sign of weak batteries. Have you purchased new batteries and installed? Are same batteries in the replacement?

I had the problem with my first one.But the new one works great.I would change it still you have a perfect one.
But first check your batteries!

Does any one know how many ohm are in the fx lightsabers ? I blew one out on mine and trying to find a replacement speaker.